A Fatigue and Fracture Study on High Strength Cast Irons

Abstract:

Fatigue strength and fracture of high strength cast irons, gray iron grade 300 and CGI grade 450, used for producing lightweight cylinder blocks, were studied. The results show endurance ratios of 0.27-0.28 and 0.38 for gray irons and CGI, respectively. The fracture surfaces in cast irons in general show the predominance of graphite and graphite/matrix interface; however, in CGI there is a larger proportion of fractured pearlitic matrix than in gray iron. This fact, and the differences in the morphology of the graphite/matrix interface, flat in gray iron, rough in CGI, explain the higher results of fatigue strength in CGI compared to gray iron. The results of fatigue strength are compared with the literature and with previous works.

• Periodical: Materials Science Forum (Volume 925)
• Pages: 296-303
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.925.296
• Online since: June 2018
• Authors: Wilson Luiz Guesser*, Luis Carlos Guedes, Ailton L. Müller, Vagner B. Demetrio, Alexsandro Rabelo
• Keywords: Compacted Graphite Iron (CGI), Fatigue, Fractography, Gray Iron

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